* My experience is that it has become harder and harder to get into "Service Mode" over the years I've been printing. My impression is that there are some good, and not so good reasons for that.
* To me, it is almost mind-boggling that you have done enough printing to fill the waste ink pads. With OEM ink? Ink level monitoring on?
* Have you really done that much printing? Like the equivalent of 1000's and 1000's of 4x6" photo printing? Thousands of b/w text pages?
* I'd check with Canon ... yesterday ... especially if this latest generation CLI-251 based printer is under warranty. Something seems wrong.
* Can you still make prints?
* If you really have done that much printing to have the ink waste pad almost full, then it might be a Very Bad Idea to reset the counter. You could end up with nasty ink where you Really, Really Don't Want It.
More info ... TMI ? ... geek alert ?
* As you may know, most ink that gets to the ink absorber is due to print-head cleanings, purgings, and borderless print overspray.
* I've never owned a BCI-6 based printer, but people I know with them seemed to have little trouble getting into Service Mode.
* My CLI-8 based iP4500 with only lights and buttons for the UI can reach Service Mode, but the steps to do this are intentionally complicated, which is probably a good thing. You really, really don't want to get into Service Mode by trial-and-error.
* My MX850 with excellent UI is difficult to get to Service Mode, compared to the iP4500. I've heard reports of people ending up with the menus / settings in Japanese from trial-and-error, but those may be "urban legends".
* I've never figured out how to get my 9000-2 into Service Mode, but would love to find out to see about waste ink pad usage, print counts, and other interesting, geeky info.
* I think I was once or twice able to get my CLI-221 generation MP990 into Service Mode, but it may have been from accidental trial-and-error. Frustrating, and, in retrospect, risky.